<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="box">box</div>
    <script>
        // function (){
        //     console.log('123');
        // }
        // var text =function(){
        //     console.log('123');
        // }
        // div.onclick = function(){
        //     console.log(123);
        // }
        var box = document.getElementById('box');
            box.onclick = function(){
            console.log('<br>123');
            }
    </script>
</body>
</html>